Laser lift-off apparatus and method of lifting-off substrate using the same

Abstract

In a laser lift-off apparatus configured to convert a first beam into a second beam having a width in a short axis direction and a long axis direction, the laser lift-off apparatus includes: a laser beam generator generating the first beam; a homogenizer homogenizing the first beam; and a wedge prism refracting at least a portion of the first beam passing through the homogenizer, wherein a beam profile of the second beam includes a first area and a second area having energy higher than that of the first area.

What is claimed is: 
     
         1 . A laser lift-off apparatus configured to convert a first beam into a second beam having a width in a short axis direction and a long axis direction, the laser lift-off apparatus comprising:
 a laser beam generator generating the first beam;   a homogenizer homogenizing the first beam; and   a wedge prism refracting at least a portion of the first beam passing through the homogenizer,   wherein a beam profile of the second beam includes a first area and a second area having energy higher than that of the first area.   
     
     
         2 . The laser lift-off apparatus of  claim 1 , wherein the wedge prism includes a first wedge prism and a second wedge prism, which are spaced apart from each other in the long axis direction. 
     
     
         3 . The laser lift-off apparatus of  claim 2 , wherein the second area includes a first sub-area and a second sub-area, which are on their opposite sides with the first area interposed therebetween,
 the first sub-area is an area formed by the first beam passing through the first wedge prism, and   the second sub-area is an area formed by the first beam passing through the second wedge prism.   
     
     
         4 . The laser lift-off apparatus of  claim 1 , wherein the beam profile of the second beam includes a third area opposite to the first area with the second area interposed therebetween, and
 the third area has energy lower than that of the first area.   
     
     
         5 . The laser lift-off apparatus of  claim 4 , wherein an energy difference between the first area and the second area is equal to an energy difference between the first area and the third area. 
     
     
         6 . The laser lift-off apparatus of  claim 1 , wherein a position of the second area in the beam profile of the second beam is determined by a position of an area where the first beam incident on the wedge prism overlaps the wedge prism. 
     
     
         7 . The laser lift-off apparatus of  claim 1 , wherein energy intensity of the second area in the beam profile of the second beam is determined by a size of an area where the first beam incident on the wedge prism overlaps the wedge prism. 
     
     
         8 . The laser lift-off apparatus of  claim 1 , further comprising a telescope lens between the laser beam generator and the homogenizer, and configured to transmit the first beam through enlargement or the same magnification. 
     
     
         9 . The laser lift-off apparatus of  claim 8 , further comprising a short axis slit between the homogenizer and the wedge prism, and configured to transmit a portion of the first beam in the short axis direction. 
     
     
         10 . The laser lift-off apparatus of  claim 9 , further comprising a short axis Fourier lens between the homogenizer and the short axis slit, and configured to allow the first beam transmitted through the telescope lens to be focused on the short axis slit along the short axis direction. 
     
     
         11 . The laser lift-off apparatus of  claim 9 , further comprising a long axis Fourier lens between the wedge prism and an image plane on which the second beam is incident, and configured to allow the first beam transmitted through the telescope lens to be focused on the image plane. 
     
     
         12 . The laser lift-off apparatus of  claim 11 , further comprising a short axis projection lens between the wedge prism and the image plane on which the second beam is incident, and configured to adjust a width of the first beam, which has passed through the short axis slit, in the short axis direction. 
     
     
         13 . The laser lift-off apparatus of  claim 1 , further comprising a beam cutter between the wedge prism and an image plane on which the second beam is incident, and configured to block a path of the first beam incident on an outer area of the second area. 
     
     
         14 . The laser lift-off apparatus of  claim 13 , further comprising a beam cancellation area outside the second area, wherein energy intensity of the beam cancellation area is lower than that of the second area. 
     
     
         15 . The laser lift-off apparatus of  claim 1 , wherein a profile shape of the second beam in the first area and the second area is a flat top shape. 
     
     
         16 . A method of lifting-off substrate, the method comprising:
 lifting-off a carrier substrate from a first substrate by irradiating a laser generated from a laser lift-off apparatus to a display device, the display device comprising:
 the carrier substrate; 
 the first substrate on the carrier substrate; 
 a barrier layer on the first substrate; and 
 a second substrate on the barrier layer, wherein 
   the barrier layer is larger than the first substrate in a plan view,   the display device includes an active area in which pixels are located, and a protruded area in which the barrier layer does not overlap the first substrate, and   energy intensity of the laser irradiated to the active area is lower than that of the laser irradiated to the protruded area.   
     
     
         17 . The method of  claim 16 , wherein
 the laser includes a first beam and a second beam,   the laser lift-off apparatus converts the first beam into the second beam having   a width in a short axis direction and a long axis direction,   the laser lift-off apparatus includes:
 a laser beam generator generating the first beam; 
 a homogenizer homogenizing the first beam; and 
 a wedge prism refracting at least a portion of the first beam passing through the homogenizer, and 
 a beam profile of the second beam includes a first area and a second area having energy higher than that of the first area. 
   
     
     
         18 . The method of  claim 17 , wherein the second beam of the first area is irradiated to the active area, and the second beam of the second area is irradiated to the protruded area. 
     
     
         19 . The method of  claim 17 , wherein a position of the second area in the beam profile of the second beam is determined by a position of an area where the first beam incident on the wedge prism overlaps the wedge prism. 
     
     
         20 . The method of  claim 17 , wherein energy intensity of the second area in the beam profile of the second beam is determined by a size of an area where the first beam incident on the wedge prism overlaps the wedge prism.